Kisspeptin-10 10mg

What is Kisspeptin-10 ?

Kisspeptin-10 (KP-10, metastin 45-54) is the C-terminal decapeptide of human kisspeptin, supplied as a 10mg lyophilised powder. Its receptor, KISS1R, is the receptor formerly called GPR54.

Its sequence is Tyr-Asn-Trp-Asn-Ser-Phe-Gly-Leu-Arg-Phe-NH₂ (YNWNSFGLRF-NH₂), 1302.5 g/mol, CAS 374675-21-5, also catalogued as kisspeptin-112-121 or metastin (45-54). KISS1R is a class A G protein-coupled receptor coupling mainly through Gq/11 and phospholipase C. Kisspeptins are RFamide peptides, named for the C-terminal arginine-phenylalanine-amide motif that carries the pharmacophore. Ohtaki et al. (Nature, 2001) isolated the parent peptide from human placenta.

Kisspeptin-10 Research Applications

• Receptor assays : kisspeptins bound rat and human GPR54 in CHO-K1 cells with low nanomolar affinity. They triggered PIP₂ hydrolysis, calcium mobilisation and ERK1/2 phosphorylation (Kotani et al., 2001).
• Structure-activity : Ala substitution at position 6 or 10 of rat kp-10 raised EC₅₀ from the 10⁻⁸ M range to above 6.46 × 10⁻⁶ M (Gutiérrez-Pascual et al., 2009).
• Conformation : NMR modelling showed a helix between Asn4 and Tyr10, which an Ala10 substitution disrupted completely (Gutiérrez-Pascual et al., 2009).
• Reproductive axis : loss-of-function GPR54 mutations cause hypogonadotropic hypogonadism (de Roux et al., PNAS, 2003).

Kisspeptin-10 is the reference agonist at KISS1R in vitro. Typical assays are radioligand binding and competition, inositol phosphate accumulation, intracellular calcium mobilisation, ERK1/2 phosphorylation, and receptor desensitisation and internalisation. KISS1 was first characterised as a melanoma metastasis-suppressor gene, and KISS1R signalling is still studied in invasion and metastasis models.

Kisspeptin-10 vs Kisspeptin-54 (Metastin)

They are different molecules cut from the same KISS1 gene product, not two names for one compound. Kotani et al. (J Biol Chem, 2001) isolated 54, 14 and 13 residue peptides from human placenta, all sharing the C-terminal RF-amide. Ohtaki et al. (Nature, 2001) named the 54 residue form metastin. Kisspeptin-10 is the last ten residues, 1302.5 g/mol, roughly a fifth of that mass.

Both act at the same receptor because the decapeptide carries the pharmacophore. Gutiérrez-Pascual et al. (Mol Pharmacol, 2009) noted that Kp-10 has higher receptor affinity and biopotency than the longer forms. They differ in synthesis cost, solubility and clearance, which is why the short form dominates in-vitro pharmacology. Cite findings for the form actually used.

Research Overview

Kisspeptin-10 is the C-terminal decapeptide of human kisspeptin, sequence Tyr-Asn-Trp-Asn-Ser-Phe-Gly-Leu-Arg-Phe-NH₂ (YNWNSFGLRF-NH₂), molecular formula C₆₃H₈₃N₁₇O₁₄, molecular weight 1302.5 g/mol, CAS 374675-21-5. It is also catalogued as kisspeptin-112-121, as metastin (45-54) and as KP-10, and anyone looking to buy kisspeptin should note that kisspeptin-10 and kisspeptin-54 are different molecules processed from the same precursor rather than two names for one compound. The parent peptide was isolated from human placenta by Ohtaki and colleagues (Nature, 2001) as the endogenous ligand of a then-orphan G protein-coupled receptor, and Kotani and colleagues (J Biol Chem, 2001) independently isolated 54-, 14- and 13-residue forms sharing a C-terminal Arg-Phe-amide, placing kisspeptin in the RFamide peptide family. All derive from proteolytic processing of the KISS1 gene product. The receptor, KISS1R and formerly GPR54, is a class A rhodopsin-like G protein-coupled receptor that couples principally through Gq/11 to phospholipase C, with inositol trisphosphate generation, intracellular calcium mobilisation and ERK1/2 phosphorylation as the standard downstream readouts in transfected cell assays. The C-terminal amide is the pharmacophore rather than an incidental modification: structure-activity work by Gutiérrez-Pascual and colleagues (Mol Pharmacol, 2009) mapped which residues of the decapeptide are required for KISS1R activation and examined the solution conformation of the sequence. The receptor's neuroendocrine significance was established by human genetics rather than by pharmacology, when de Roux and colleagues (PNAS, 2003) identified loss-of-function KISS1R mutations in hypogonadotropic hypogonadism, placing the receptor upstream of GnRH neurons in the hypothalamus. Separately, KISS1 was first characterised as a melanoma metastasis-suppressor gene, and KISS1/KISS1R signalling remains an active cancer-biology literature.

Storage and Reconstitution

Store the sealed 10mg vial at -20°C, dry and away from light. Keep reconstituted solution at 2-8°C in a light-protected container and freeze single-use aliquots for longer storage. Two degradation routes matter here: tryptophan oxidation, and hydrolysis of the C-terminal phenylalanine amide, which gives a free acid one mass unit heavier and much less active at KISS1R. Mass spectrometry after long storage is the practical check.

Vials are sold on their own, without bacteriostatic water for mixing or other supplies.

How to reconstitute and handle

Let the vial reach room temperature. Run bacteriostatic water slowly down the inside wall of the vial and swirl gently until clear and colourless, without shaking. Work away from direct sunlight and fluorescent light: tryptophan 3 is the most oxidation-sensitive residue and its oxidation shows up as a new RP-HPLC peak. Label the vial with the reconstitution date and refrigerate it.

• Allow the vial to reach room temperature before opening so condensation does not settle on the powder.
• Protect from light throughout handling. The sequence carries a tryptophan at position 3 and two aromatic phenylalanines, and tryptophan oxidation is the degradation route most often picked up as a new RP-HPLC peak in stored aromatic peptides.
• Treat the C-terminal amide as an integrity checkpoint, not a detail. Because amidation of the terminal phenylalanine is required for KISS1R activation, hydrolysis of that amide converts the peptide to a substantially less active free acid one mass unit heavier, which is worth confirming by mass spectrometry after extended storage.
• Avoid repeated freeze-thaw cycles and repeated stopper punctures.
• For cell work note that kisspeptin is reported to be rapidly cleaved by proteases including matrix metalloproteinases, so incubation time and serum content of the medium will both affect the concentration actually present at the receptor.

For the full method, see the peptide reconstitution guide and the reconstitution calculator.

Research References

• Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor (Ohtaki et al., Nature, 2001)
• The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54 (Kotani et al., J Biol Chem, 2001)
• Hypogonadotropic hypogonadism due to loss of function of the KiSS1-derived peptide receptor GPR54 (de Roux et al., PNAS, 2003)
• In vivo and in vitro structure-activity relationships and structural conformation of Kisspeptin-10-related peptides (Gutiérrez-Pascual et al., Mol Pharmacol, 2009)

Published research on Kisspeptin-10 is indexed on PubMed. See our full UK buyer's guide for Kisspeptin-10 and UK buyer's guide for Kisspeptin-10 CoA.